The world and more importantly the wealthy are vastly richer today than in 1976 when the concord started flying, and the R&D costs should be far lower. There’s

The world and more importantly the wealthy are vastly richer today than in 1976 when the concord started flying, and the R&D costs should be far lower. There’s thousands of billionaires in the world. Not all of them would buy a supersonic private airplane, but include non billionaire CEO’s etc and the market is plenty large to support moderate scale production assuming they can keep costs within a fairly low multiple of a business jet.